JP2017127287A - Paddy working machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a back clutch be controlled into an on-state after a continuously variable transmission becomes a forward drive state when the continuously variable transmission is switched from a reverse drive state to the forward drive state, in a paddy working machine in which the back clutch is switched and controlled between an on-state and an off-state based on detection results of operation position of a gear shift lever.SOLUTION: A gear shift lever 40 can be operated over a neutral operation position nf of the forward side facing a forward operation area F and a neutral operation position nr of the reverse side facing a reverse operation level R in a neutral operation area N. When the gear shift lever 40 is positioned in the neutral operation area N, a clutch control mechanism 50 switches and controls the back clutch 31 to an off-state regardless of the movement over the neutral operation position nf of the forward side of the gear shift lever 40 and the neutral operation position nr of the reverse side.SELECTED DRAWING: Figure 6

Description

  The present invention includes a paddy field machine, and more specifically, a continuously variable transmission that continuously drives and drives a traveling device, the forward operation region in which the continuously variable transmission is shifted to a forward drive state, and the continuously variable A reverse operation range for shifting the transmission to the reverse drive state, and a neutral operation range that is located between the forward operation range and the reverse operation range and for shifting the continuously variable transmission to the neutral state. The present invention relates to a paddy field work machine provided with a shift lever that is manually operated.

  In the above-described riding type rice transplanter as a paddy field work machine, conventionally, as shown in, for example, Patent Document 1, a driving force is transmitted to a seedling planting device as a working unit by being switched to the on state, and the cut state is set. It is equipped with a back clutch that releases transmission of driving force to the seedling planting device by being switched, and is equipped with a linkage mechanism that links the on / off operation of the back clutch and the switching operation of the main transmission lever, In some cases, the clutch is switched to the engaged state by the linkage mechanism to drive the seedling planting device, and during reverse travel, the back clutch is switched to the disconnected state by the linkage mechanism to stop the seedling planting device.

  Specifically, in the technique disclosed in Patent Document 1, a detection lever that swings in contact with the main transmission lever and detects an operation toward the reverse transmission position side of the main transmission lever is provided to be swingable. A detection lever and a swing operation member that engages and disengages the back clutch are interlocked and connected via a connecting rod and a bell crank.

Japanese Patent Laying-Open No. 2015-113961

  When the conventional technology is used to control the switching of the back clutch between the engaged state and the disengaged state based on the detection result of the operation position of the shift lever, when switching from backward traveling to forward traveling, continuously variable The back clutch is switched to the engaged state at the timing until the transmission is switched to the forward drive state, that is, the timing at which the continuously variable transmission is still in the neutral state.

  That is, the operation area of the shift lever includes a forward operation area, a reverse operation area, and a neutral operation area extending from the forward neutral operation position facing the forward operation area to the reverse neutral operation position facing the reverse operation area. Is set. When the conventional technology is employed, when the speed change lever is positioned in the reverse operation range and the neutral operation position on the reverse side, the detection lever contacts the speed change lever and the back clutch is controlled to be disengaged. However, since the detection lever does not move to the forward operation range and the forward-side neutral operation position, that is, the forward operation region and the forward-side neutral operation position are outside the detection target range of the detection lever, the shift lever moves backward. By moving from the neutral operation position on the side to the neutral operation position on the forward side, the back clutch is switched to the engaged state and controlled.

When the shift lever is positioned at the forward-side neutral operation position and the back clutch is switched to the engaged state, the working unit can be driven even though the shift lever is positioned at the forward-side neutral operation position. May be.
In other words, in the case where the output of the continuously variable transmission is transmitted to the working unit, a poor linkage between the transmission lever and the continuously variable transmission occurs, and the continuously variable transmission is performed even if the transmission lever is located at the forward neutral operation position. If the device is not in the neutral state and remains in the transmission state, the working unit may be driven even though the shift lever is positioned at the forward neutral position.

  In the present invention, the back clutch is controlled to be engaged based on the detection result of the operation position of the transmission lever during forward travel, and the back clutch is disengaged based on the detection result of the operation position of the transmission lever during reverse travel. When switching from reverse travel to forward travel, a paddy field work machine is provided in which the back clutch is not controlled to be engaged until the continuously variable transmission is in the forward drive state.

A paddy field work machine according to the present invention includes a continuously variable transmission that continuously drives and drives a traveling device;
Positioned between a forward operation range for shifting the continuously variable transmission to a forward drive state, a reverse operation range for shifting the continuously variable transmission to a reverse drive state, and the forward operation region and the reverse operation region. And a neutral operation range in which the continuously variable transmission is shifted to a neutral state, and a shift lever that is operated by human operation,
A back clutch that transmits the driving force to the working unit by being switched to the on state, and that cancels transmission of the driving force to the working unit by being switched to the off state;
A clutch control mechanism that detects an operation position of the shift lever and switches and controls the back clutch based on a detection result;
In the neutral operation area, the shift lever is operable over a forward neutral operation position facing the forward operation area and a reverse neutral operation position facing the reverse operation area.
When the shift lever is positioned in the forward operation range, the clutch control mechanism controls the back clutch to be switched to the engaged state,
When the speed change lever is positioned in the neutral operation range, the clutch control mechanism disengages the back clutch regardless of movement of the speed change lever between the forward neutral position and the reverse neutral position. Control to switch to the state,
When the shift lever is positioned in the reverse operation area, the clutch control mechanism controls the back clutch to be switched to the disengaged state.

  According to this configuration, when the shift lever is operated to the forward operation range, the back clutch is controlled to be engaged by the clutch control mechanism, and when the shift lever is operated to the reverse operation range, the back clutch is disconnected by the clutch control mechanism. Controlled by the state.

  In order to switch the continuously variable transmission from the reverse drive state to the forward drive state, the speed change lever is operated from the reverse operation region to the reverse side neutral operation position to the forward side neutral operation position, and the forward side neutral operation position. To the forward operation range. The back clutch is still switched to the disengaged state when the shift lever is positioned at the reverse side neutral operation position or the forward side neutral operation position, and the shift lever is positioned in the forward operation range. For the first time, the back clutch is controlled to be engaged.

  Therefore, in forward travel, the back clutch can be controlled to be engaged and the working unit can be driven, and in reverse travel, the back clutch can be controlled to be disengaged and the work unit can be stopped. When switching, the back clutch is still in the disengaged state even if the continuously variable transmission switches from the reverse drive state to the neutral state, and the back clutch is not started until the continuously variable transmission switches from the neutral state to the forward drive state. Is switched to the engaged state, so that the back clutch is not engaged in the neutral state before switching to forward travel, and the risk of the working unit being driven in the stopped state can be avoided.

  In the present invention, the clutch control mechanism includes a detection body provided on the lateral side of the operation path of the shift lever so as to be swingable across a clutch engagement command area and a clutch disengagement command area, and the detection body. An urging mechanism that swings and urges the clutch engagement command area, and when the shift lever is positioned in the neutral operation area and the reverse operation area, the clutch disengagement command area is pressed by the shift lever. When the shift lever is positioned in the forward operation range, it is preferable that the detection body is swinged to the clutch engagement command range by the biasing mechanism.

  According to this configuration, the detection body is provided on the lateral side of the operation path so as to be swingable, and a simple and inexpensive structure that simply includes a biasing mechanism that swings and biases the detection body to the clutch engagement command area. The back clutch can be held in the disengaged state until the transmission is switched to the forward drive state.

It is a right view which shows the whole riding type rice transplanter. It is a block diagram which shows the power transmission system which transmits a driving force to a front wheel, a rear wheel, and a seedling planting apparatus. It is a diagram which shows the power transmission system which transmits a driving force to a front wheel and a rear wheel. It is a diagram which shows the power transmission system which transmits a driving force to a seedling planting apparatus. It is explanatory drawing which shows the clutch control mechanism of the state in which a transmission lever is located in a forward operation area. It is explanatory drawing which shows the clutch control mechanism of the state in which the speed-change lever is located in the forward neutral position. It is explanatory drawing which shows the clutch control mechanism in the state in which the speed-change lever is located in the reverse side neutral operation position. It is explanatory drawing which shows the clutch control mechanism of the state in which a transmission lever is located in a reverse operation area. It is explanatory drawing which shows the clutch control mechanism of the state in which a transmission lever is located in a reverse operation area. It is sectional drawing which shows a fraction strip clutch. It is a XI-XI cross-sectional arrow view of FIG. It is a top view which shows a passive rotary body. It is explanatory drawing which shows the operation position of a work lever. It is explanatory drawing which shows the operation position of the operation lever of the riding type rice transplanter provided with another implementation structure.

  Hereinafter, a case where an embodiment of a paddy field working machine according to the present invention is applied to a riding type rice transplanter as an example of a paddy field working machine will be described based on the drawings. FIG. 1 is a right side view showing the entire riding rice transplanter.

  As shown in FIG. 1, the riding type rice transplanter includes a traveling vehicle body 4 provided with a pair of left and right front wheels 2 (traveling device) and a pair of left and right rear wheels 3 (traveling device) at the lower part of a body frame 1. Yes. A driving portion 6 having an engine 5 is provided at the front portion of the traveling vehicle body 4. The traveling vehicle body 4 is self-propelled when the left and right front wheels 2 and the left and right rear wheels 3 are driven by the driving force from the engine 5. A driving unit 8 having a driving seat 7 is provided at the rear of the traveling vehicle body 4. The traveling vehicle body 4 is of a riding type so as to be mounted on and operated by the driving unit 8.

  A seedling planting device 10 (working unit) is connected to the rear portion of the traveling vehicle body 4 via a link mechanism 9. The seedling planting device 10 includes a plurality of grounding floats 11 arranged in the width direction of the traveling vehicle body 4, a plurality of seedling planting mechanisms 12 arranged in the width direction of the traveling vehicle body 4, and a seedling supplied to the seedling planting mechanism 12. A mounting table 13 is provided. The grounding float 11 is supported at the lower part of the planting frame 14. The link mechanism 9 extends from the traveling vehicle body 4 so as to be swingable up and down. In the seedling planting device 10, the link mechanism 9 is operated to swing by the hydraulic cylinder 9a, so that the grounding float 11 is in a descending work state in which the grounding float 11 is in contact with the field scene and the grounding float 11 is in the state in which the grounding float 11 is lifted from the field scene The lift operation is performed over the lifted non-working state.

  The riding type rice planting machine lowers the seedling planting device 10 to a lowering operation state, and causes the traveling vehicle body 4 to travel in this state, thereby performing a plurality of rice seedling planting operations by the seedling planting device 10.

  The driving force is transmitted to the front wheel 2 and the rear wheel 3 based on the power transmission system shown in FIGS. That is, the driving force of the output shaft 5 a of the engine 5 is transmitted to the input shaft 21 a of the continuously variable transmission 21 via the endless belt 20, and the driving force of the output shaft 21 b of the continuously variable transmission 21 is input to the auxiliary transmission 22. Is done. The output of the auxiliary transmission 22 is input to the traveling auxiliary transmission 23, and the output of the traveling auxiliary transmission 23 is input to the front wheel differential mechanism 24. The driving force of the left and right output shafts 24 a of the front wheel differential mechanism 24 is transmitted to the left and right front wheels 2 via the left and right front wheel drive cases 25. The output of the traveling auxiliary transmission 23 is taken out from the transmission case 27 by the power take-off shaft 26, and the taken drive force is transmitted to the input shaft 29 a of the rear wheel drive case 29 through the rotary shaft 28. The driving force of the input shaft 29a is distributed and transmitted to the left and right rear wheels 3, 3 by the rotating shaft 30.

  The continuously variable transmission 21 is a hydrostatic continuously variable transmission. The continuously variable transmission 21 drives the front wheels 2 and the rear wheels 3 forward by being shifted in the forward drive state, and the front wheels 2 and the rear wheels 3 by being shifted in the reverse drive state. Is driven to the reverse side and the front wheel 2 and the rear wheel 3 are stopped by shifting the vehicle to a neutral state. The neutral state is located between the forward drive state and the reverse drive state. The continuously variable transmission 21 shifts and drives the front wheels 2 and the rear wheels 3 steplessly in both the forward drive state and the reverse drive state.

  The auxiliary transmission 22 is shifted to a two-stage transmission state of high speed and low speed by a sliding operation of the shift gear 22a. The traveling sub-transmission device 23 is shifted to a high-speed and low-speed transmission state by a slide operation of the shift gear 23a. The front wheel 2 and the rear wheel 3 can be sub-shifted in four stages by combining the two-stage shift of the sub-transmission device 22 and the two-stage shift of the traveling sub-transmission device 23.

  The driving force is transmitted to the seedling planting device 10 based on the power transmission system shown in FIGS. That is, the output of the auxiliary transmission 22 is input to the back clutch 31, and the output of the back clutch 31 is input to the first planting transmission 33 via the torque limiter 32. The output of the first planting transmission 33 is input to the second planting transmission 34, and the output of the second planting transmission 34 is input to the planting clutch 35. The output of the planting clutch 35 is extracted from the transmission case 27 by the power extraction shaft 36, and the extracted driving force is transmitted to the input shaft 10 a of the seedling planting device 10 via the rotating shaft 37.

  When the back clutch 31 is switched to the engaged state, the output of the auxiliary transmission 22 is transmitted to the torque limiter 32, thereby transmitting the driving force to the seedling planting device 10. When the back clutch 31 is switched to the disengaged state, the transmission of the driving force from the auxiliary transmission 22 to the torque limiter 32 is cut off, thereby releasing the transmission of the driving force to the seedling planting device 10.

  The planting clutch 35 is switched between the on state and the off state by the sliding operation of the shifter 35b by the operation rod 35a. The planting clutch 35 is operated to be switched to the engaged state, thereby transmitting the output of the second planting transmission device 34 to the power take-out shaft 36, thereby transmitting the driving force to the seedling planting device 10. When the planting clutch 35 is switched to the cut-off state, the transmission of the driving force from the second planting transmission 34 to the power take-off shaft 36 is cut off, so that the driving force is transmitted to the seedling planting device 10. Is released.

  The first planting transmission 33 can shift in two stages, a high speed and a low speed, by a sliding operation of the shift gear 33b by the shift lever 33a. The second planting transmission 34 can shift to a four-stage shift state by a slide operation of the shift key 34b by the shift lever 34a. By combining the two-stage shifting of the first planting transmission 33 and the four-stage shifting of the second planting transmission 34, the drive speed of the seedling planting apparatus 10 can be shifted in eight stages, and the size between the plants can be increased by eight. It can be changed.

  As shown in FIG. 2, the planting clutch 35 is provided with a check mechanism 38. A detection switch 39 is linked to the incoming check mechanism 38. The detection switch 39 detects whether the traveling sub-transmission device 23 is operated in a high-speed or low-speed transmission state based on the operation position of the sub-transmission lever 23b that performs a shifting operation on the traveling sub-transmission device 23. In other words, when the sub transmission lever 23b is operated to the high speed position [H], the detection switch 39 is brought into contact with the detection portion of the detection switch 39 so that the traveling sub transmission 23 is in a high speed transmission state. A fast detection state is detected when it is operated. When the auxiliary transmission lever 23b is operated to the low speed position [L], the detection switch 39 releases the contact between the auxiliary transmission lever 23b and the detection portion of the detection switch 39, so that the traveling auxiliary transmission 23 is operated at a low speed. When operating in the transmission state, the low speed detection state is detected. When the detection switch 39 is in a high-speed detection state, the entrance check mechanism 38 switches to an on state based on information from the detection switch 39 and uses it for the planting clutch 35 to return the planting clutch 35 to the engaged state. Disable switching. When the detection switch 39 enters the low speed detection state, the entrance check mechanism 38 switches to the off state based on the information from the detection switch 39 to release the check production for the planting clutch 35 and the planting clutch 35 enters. Allows switching to a state.

  If the traveling sub-transmission 23 is shifted to the low-speed transmission state, the entering check mechanism 38 is switched to the off state, and the planting clutch 35 can be operated to the on state, and seedling planting work can be performed. Attempting to plant seedlings while the traveling sub-transmission device 23 that has been shifted to the high-speed transmission state at the time of moving traveling is kept in that shifting state, or erroneously puts the traveling sub-transmission device 23 into the high-speed transmission state during the seedling planting operation. When shifting, the entering check mechanism 38 switches to the on state and the planting clutch 35 cannot be operated to the on state, so that the seedling planting device 10 cannot be driven.

  When the shift to the high speed transmission state of the traveling sub-transmission device 23 and the switching to the engaged state of the planting clutch 35 occur, a warning sound is generated or an error display is generated. When the device 23 is shifted to the high speed transmission state, a configuration in which an operation command for switching the planting clutch 35 to the on state is canceled may be adopted instead of the on and check mechanism 38.

  As shown in FIG. 2, a shift lever 40 is linked and connected to the shift operation portion of the continuously variable transmission 21. The speed change operation unit changes the speed of the continuously variable transmission 21 by changing the swash plate angle of the hydraulic pump 21 c constituting the continuously variable transmission 21. The speed change operation unit and the speed change lever 40 are interlocked and connected by a mechanical interlocking mechanism 41 using a swing link (not shown), a rod (not shown), or the like. As shown in FIG. 1, the transmission lever 40 is supported by a lateral side portion of the steering handle 42 in the driving unit 8. The continuously variable transmission 21 can be speed-changed by swinging the speed change lever 40 in the operation path 43 shown in FIG.

  That is, as shown in FIGS. 5 to 9, the forward operation area F is set on one end side portion of the operation path 43, the neutral operation area N is set on the intermediate portion of the operation path 43, and the other end side of the operation path 43. The reverse operation area R is set in the part. The forward operation area F and the reverse operation area R are set so as to extend in the front-rear direction of the traveling vehicle body 4. The neutral operation area N is set so as to extend in the lateral width direction of the traveling vehicle body 4. The neutral operation area N is provided with a forward neutral operation position nf facing the forward operation area F and a reverse neutral operation position nr facing the reverse operation area R in different operating positions.

  As shown in FIG. 5, by operating the shift lever 40 to the forward operation range F, the continuously variable transmission 21 can be shifted to the forward drive state. In the forward operation range F, the stepless transmission 21 can be shifted to a higher speed in the forward drive state as the shift lever 40 is moved closer to the end opposite to the neutral operation range.

  As shown in FIGS. 6 and 7, by operating the shift lever 40 to the neutral operation range N, the continuously variable transmission 21 can be shifted to the neutral state. Even if the shift lever 40 is moved between the forward-side neutral operation position nf and the reverse-side neutral operation position nr, the continuously variable transmission 21 can be shifted to the neutral state.

  As shown in FIGS. 8 and 9, by operating the shift lever 40 to the reverse operation range R, the continuously variable transmission 21 can be shifted to the reverse drive state. In the reverse operation region R, the stepless transmission 21 can be shifted to a higher speed in the reverse drive state as the shift lever 40 is moved closer to the end opposite to the neutral operation region.

  As shown in FIGS. 2 and 5 to 9, the back clutch 31 and the transmission lever 40 are linked by a clutch control mechanism 50. When the speed change lever 40 is positioned in the forward operation range F as shown in FIG. 5, the clutch control mechanism 50 controls to switch the back clutch 31 to the engaged state. 6 and 7, the clutch control mechanism 50 moves the shift lever 40 between the forward-side neutral operation position nf and the reverse-side neutral operation position nr when the shift lever 40 is positioned in the neutral operation area N. Regardless, the back clutch 31 is switched to the disengaged state. The clutch control mechanism 50 switches the back clutch 31 to the disengaged state when the speed change lever 40 is positioned in the reverse operation range R as shown in FIGS.

  That is, when performing seedling planting work, the continuously variable transmission 21 is shifted to the forward drive state. In this case, since the back clutch 31 is engaged by the control of the clutch control mechanism 50, by shifting the traveling auxiliary transmission 23 to the low-speed transmission state, the engagement check mechanism 38 is turned off and the planting clutch 35 is turned on. Can be switched to the on state, so that the seedling planting device 10 can be driven.

  In the case of reverse travel, the seedling planting apparatus 10 can be stopped because the back clutch 31 is disengaged by control by the clutch control mechanism 50 only by shifting the continuously variable transmission 21 to the reverse drive state.

  When the traveling vehicle body 4 is stopped, when the speed change lever 40 is operated to the neutral operation range N, the speed change lever 40 is located at any neutral operation position in the range from the forward neutral operation position nf to the reverse neutral operation position nr. Even if it is positioned, the back clutch 31 is disengaged by the control by the clutch control mechanism 50. That is, the seedling planting device 10 can be reliably stopped only by shifting the continuously variable transmission 21 to the neutral state.

  Specifically, the clutch control mechanism 50 includes a detection unit 51 and a control unit 56 as shown in FIGS.

  The detection unit 51 includes a detection body 52 and a spring 53. The detection body 52 is supported on the lateral side of the operation path 43 so as to be swingable via a support shaft 54, and the clutch engagement command area A and the clutch disengagement shown in FIG. It swings over the command area B. A first detection portion 52 a and a second detection portion 52 b are formed on one free end side portion of the detection body 52. The 1st detection part 52a is located in the location closer to the rocking | swiveling center P than the 2nd detection part 52b. The first detection unit 52a protrudes toward the operation path 43 from the second detection unit 52b. The spring 53 urges the detection body 52 to swing to the clutch engagement command area A. In this embodiment, the spring 53 is employed as the urging mechanism, but various urging means such as rubber may be employed instead of the spring 53.

  As shown in FIG. 5, when the speed change lever 40 is operated in the forward operation range F, the second detection portion 52b is received and supported by the stopper 55, and the first detection portion 52a is not subjected to a pressing operation by the speed change lever 40. The detection body 52 is in a detection state for detecting that the shift lever 40 is positioned in the forward operation range F. When detecting that the shift lever 40 is positioned in the forward operation region F, the detection body 52 is positioned in the clutch engagement command region A and is operated to switch the back clutch 31 to the engaged state by the swinging urging force of the spring 53. A clutch engagement operating force as a clutch engagement command to be performed is applied to the control unit 56.

  As shown in FIGS. 6 and 7, when the speed change lever 40 is operated in the neutral operation range N, the first detection unit 52 a comes into contact with the speed change lever 40 and receives a pressing operation by the speed change lever 40. In this state, the shift lever 40 is detected to be positioned in the neutral operation area N. When detecting that the shift lever 40 is positioned in the neutral operation range N, the detection body 52 is moved away from the clutch engagement command range A by the pressing operation by the shift lever 40 and is positioned in the clutch release command range B. A clutch disengagement operation force as a disengagement command is applied to the control unit 56.

  As shown in FIGS. 6 and 7, even if the shift lever 40 is moved between the forward-side neutral operation position nf and the reverse-side neutral operation position nr, the first detection unit 52 a performs the pressing operation by the shift lever 40. Therefore, the detection body 52 deviates from the clutch engagement command area A, is positioned in the clutch disconnection instruction area B, and applies a clutch disconnection operation force as a clutch disconnection instruction to the control unit 56.

  As shown in FIGS. 8 and 9, when the shift lever 40 is operated in the reverse operation range R, the first detection unit 52 a contacts the shift lever 40 and receives a pressing operation by the shift lever 40, or the second Since the detection unit 52b comes into contact with the speed change lever 40 and receives a pressing operation by the speed change lever 40, the detection body 52 is in a detection state for detecting that the speed change lever 40 is positioned in the reverse operation range R. When detecting that the shift lever 40 is positioned in the reverse operation range R, the detection body 52 is moved away from the clutch engagement command range A by the pressing operation by the shift lever 40 and is positioned in the clutch disconnection command range B. A clutch disengagement operation force as a command is applied to the control unit 56.

  As shown in FIGS. 5 to 9, the control unit 56 includes a clutch control member 57, and operates the clutch control member 57 with the clutch disengagement operation force and the clutch engagement operation force applied by the detection body 52 to operate the back clutch. 31 is switched to the on state or is switched to the off state.

  That is, the clutch control member 57 is attached across the detection body 52 and the operation arm 31 a of the back clutch 31. The end of the clutch control member 57 on the detection body side is moved relative to the free end side of the detection body 52 opposite to the side where the first detection section 52a and the second detection section 52b are located via a connecting pin 58. It is linked movably. An elongated hole 59 is formed at the end of the clutch control member 57 on the operation arm side. A connecting pin 31b slidably engaged with the elongated hole 59 is fixed to the operation arm 31a.

  As shown in FIGS. 5 to 9, the operation arm 31 a is supported on the outside of the transmission case 27 through a shifter support shaft 31 c so as to be swingable, and a clutch engagement position with the shaft core of the shifter support shaft 31 c as a swing center. Swings between [On] and the clutch disengagement position [Off]. When the operation arm 31a is operated to the clutch engagement position [on], the shifter support shaft (not shown) is rotated to switch the back clutch 31 to the engagement state. The operation arm 31a is operated to the clutch disengagement position [disengagement], thereby rotating the shifter support shaft to switch the back clutch 31 to the disengagement state. The operating arm 31a is urged to swing to the clutch disengagement position [disengagement] by a disengagement biasing means (not shown). The cutting biasing means is provided inside the mission case 27.

  As shown in FIG. 5, when the shift lever 40 is operated in the forward operation range F and the detection body 52 is positioned in the clutch engagement command area A, the clutch control member 57 is operated by the clutch engagement operation force by the detection body 52. Since the portion of the clutch control member 57 located at the end of the long hole 59 presses the connecting pin 31b, the clutch control member 57 cuts the operation arm 31a against the biasing means. Operate the clutch engaged position [ON].

  As shown in FIGS. 6 and 7, when the shift lever 40 is operated in the neutral operation area N and the detection body 52 is positioned in the clutch release command area B, the clutch control member 57 is operated by the clutch release operation force of the detection body 52. Since the elongate hole portion is operated to be pulled opposite to the arm 31a side and the pressing operation of the connecting pin 31b is released, the clutch control member 57 operates the operation arm 31a to the clutch disengagement position [disengagement] by the disengagement means. Even if the shift lever 40 is moved between the forward neutral operation position nf and the reverse neutral operation position nr, the detection body 52 is positioned in the clutch disengagement command area B, and the clutch control member 57 is operated by the operation arm 31a. Since the elongated hole 59 is moved while leaving the connecting pin 31b by being pulled to the opposite side, the clutch control member 57 maintains the operation arm 31a at the clutch disengaged position [disengaged].

  As shown in FIGS. 8 and 9, when the shift lever 40 is operated in the reverse operation range R and the detection body 52 is positioned in the clutch disengagement command range B, it is the same as when the shift lever 40 is operated in the neutral operation range N. In addition, the clutch control member 57 is pulled to the opposite side to the operation arm 31a side by the clutch disengagement operation force by the detection body 52, and the elongated hole 59 leaves the connection pin 31b, so that the clutch control member 57 moves the operation arm 31a. It is operated to the clutch disengagement position [disengagement] by the disengagement biasing means.

  FIG. 10 is a cross-sectional view showing the fractional clutch 60. The fraction clutch 60 is switched to the on state to transmit the driving force of the input shaft 10a to two adjacent seedling planting mechanisms 12 among the plurality of seedling planting mechanisms 12, thereby The planting mechanism 12 is driven. The fraction clutch 60 is switched to the disengaged state, thereby stopping the transmission of the driving force to the two seedling planting mechanisms 12 and stopping the two seedling planting mechanisms 12. The fractional clutch 60 has a fixed position stop function for maintaining the seedling planting mechanism 12 in a stopped state at a rotational phase where the planting claws 12a (see FIG. 1) are projected upward from the mud portion of the field. .

  As shown in FIG. 10, the fractional clutch 60 includes a drive rotator 61, a passive rotator 62, and a mesh type clutch body 63. The clutch body 63 is provided across the drive rotator 61 and the passive rotator 62. The drive rotator 61 is supported at the end of the output side rotating shaft 64 so as to be relatively rotatable. The drive rotator 61 is linked to the input shaft 10a (see FIG. 4) via the gear 65 and the input-side rotation shaft 66, and is driven by the driving force of the input shaft 10a. The output-side rotating shaft 64 is linked to two seedling planting mechanisms 12 (see FIG. 1) adjacent to each other at the end opposite to the end supporting the drive rotating body 61.

  The passive rotating body 62 is supported by the spline portion 64a of the output side rotating shaft 64 so as not to be relatively rotatable and to be slidable. A spring 67 is mounted across the side of the passive rotating body 62 opposite to the clutch main body 63 and the spring receiving portion 64b of the output-side rotating shaft 64. The spring 67 slidably biases the passive rotator 62 toward the drive rotator 61 and urges the clutch body 63 into the engaged state. An operation recessed portion 68 as shown in FIGS. 11 and 12 is formed on the periphery of the passive rotating body 62. An inclined cam surface 69, a positioning surface 70 and a stopper 71 are provided inside the operation recess 68. The inclined cam surface 69 is inclined with respect to the rotational direction Z of the passive rotating body 62 as shown in FIG. As shown in FIGS. 11 and 12, the positioning surface portion 70 is located on the upper side in the rotational direction of the passive rotating body 62 with respect to the inclined cam surface portion 69. As shown in FIG. 10, the operation pin 73 is supported on the cylindrical support portion 72 a of the power transmission case 72 so as to be slidable in the radial direction of the passive rotating body 62.

  When the operation pin 73 is slid toward the passive rotating body 62 and the tip 73a of the operating pin 73 enters the operation recessed portion 68, the passive rotating body 62 rotates with the inclined cam surface portion 69 while rotating in the rotation direction Z. The tip 73a of the pin 73 abuts, and the passive rotating body 62 is slid to the side away from the driving rotating body 61 against the spring 67 by the cutting operation force generated by the cam action of the inclined cam surface 69, and the clutch The main body 63 is turned off. That is, the fractional clutch 60 is switched to the disengaged state. When the seedling planting mechanism 12 reaches the rotational phase for stopping, the distal end portion 73a is positioned on the positioning surface portion 70, and the distal end portion 73a contacts the stopper portion 71 to position the passive rotating body 62.

  When the operation pin 73 is slid in a direction away from the passive rotator 62 and the tip end portion 73a is extracted from the operation recess 68, the passive rotator 62 is slid toward the drive rotator 61 by the spring 67. The clutch body 63 is engaged. That is, the fraction clutch 60 is switched to the engaged state. When the positioning surface portion 70 is inclined with respect to the radial direction of the passive rotating body 62, the positioning surface portion is moved when the operation pin 73 is operated to come out of the operation recessed portion 68 and the tip end portion 73 a slides on the positioning surface portion 70. Due to the inclination of 70, the passive rotating body 62 may slide toward the driving rotating body 61 by the operating force of the spring 67, and the clutch main body 63 may start to bite before the operating pin 73 comes out of the operating recess 68. Easy to come out. As shown in FIGS. 10 and 12, the positioning surface portion 70 extends along the radial direction of the passive rotating body 62. Thereby, when the tip end portion 73 a slides on the positioning surface portion 70, the passive rotating body 62 is not slid toward the driving rotating body 61 by the spring 67. That is, the passive rotating body 62 is slid to the drive rotating body 61 only after the operation pin 73 has been removed from the operation recess 68, and the clutch body 63 bites before the operation pin 73 does not come out of the operation recess 68. The risk of matching can be reduced.

  FIG. 13 is an explanatory diagram showing the operation position of the work lever 77. As shown in FIG. 13, the seedling planting apparatus 10 is moved up and down between the non-lifting state and the lowering working state by switching the operation lever 77 between the rising position [raising] and the lowering position [lowering]. it can. By operating the working lever 77 to the neutral position [N], the raising and lowering planting device 10 can be stopped at an arbitrary position. By operating the work lever 77 from the lowered position [down] to the first planting position [planting I] after passing the left marker position [left marker], the left drawing marker can be put into the lowered use state. At the same time, the planting clutch 35 can be switched to the engaged state. The right drawing marker 78 (see FIG. 1) is moved downward by operating the work lever 77 from the lowered position [down] to the second planting position [planting II] after passing the right marker position [right marker]. The planting clutch 35 can be switched to the engaged state.

[Another Example]
(1) FIG. 14 is an explanatory view showing the operation position of the work lever 77 of the riding type rice transplanter having another implementation structure. In the riding type rice transplanter having another implementation structure, the left lever is drawn by operating the work lever 77 from the lowered position [down] to the left position [left marker] to the planting position [planting]. The marker can be put into the lowered use state and the planting clutch 35 can be switched to the on state. By operating the working lever 77 from the lowered position [downward] to the planting position [planting] after passing the right marker position [right marker], the right drawing marker 78 can be put into the lowered use state and planted. The attached clutch 35 can be switched to the engaged state.

(2) In the above-described embodiment, the operation path 43 is configured such that the forward operation area F and the reverse operation area R are displaced in the lateral width direction of the traveling vehicle body 4, and the neutral operation area N is the lateral width of the traveling vehicle body 4. Although an example extending in the direction is shown, the forward operation area F and the reverse operation area R are aligned in the longitudinal direction of the traveling vehicle body 4, and the neutral operation area N travels along the forward operation area F and the reverse operation area R. A configuration extending in the front-rear direction of the vehicle body 4 may be employed.

(3) In the above-described embodiment, the back clutch 31 is provided on the upper side in the power transmission direction with respect to the first planting transmission device 33, the second planting transmission device 34, and the planting clutch 35. Not limited to the above, between the first planting transmission 33 and the second planting transmission 34, between the second planting transmission 34 and the planting clutch 35, the lower side in the transmission direction from the planting clutch 35, etc. , It may be provided at any location.

(4) In the above-described embodiment, an example in which the traveling vehicle body 4 includes the front wheels 2 and the rear wheels 3 has been shown. However, instead of the wheels, a crawler traveling device or a traveling device combining a crawler and wheels, etc. You may implement with various traveling apparatuses.

  INDUSTRIAL APPLICABILITY The present invention can be applied to various paddy field work machines including various paddy field working units, such as a direct seeding machine including a seeding device, in addition to a riding type rice transplanter.

10 Working department (seedling planting device)
21 continuously variable transmission 31 back clutch 40 shift lever 43 operation path 50 clutch control mechanism 52 detector 53 biasing mechanism (spring)
A Enter command area B Cut command area F Forward operation area N Neutral operation area nf Forward side neutral operation position nr Reverse side neutral operation position

Claims (2)

A continuously variable transmission that continuously drives and drives the traveling device;
Positioned between a forward operation range for shifting the continuously variable transmission to a forward drive state, a reverse operation range for shifting the continuously variable transmission to a reverse drive state, and the forward operation region and the reverse operation region. And a neutral operation range in which the continuously variable transmission is shifted to a neutral state, and a shift lever that is operated by human operation,
A back clutch that transmits the driving force to the working unit by being switched to the on state, and that cancels transmission of the driving force to the working unit by being switched to the off state;
A clutch control mechanism that detects an operation position of the shift lever and switches and controls the back clutch based on a detection result;
In the neutral operation area, the shift lever is operable over a forward neutral operation position facing the forward operation area and a reverse neutral operation position facing the reverse operation area.
When the shift lever is positioned in the forward operation range, the clutch control mechanism controls the back clutch to be switched to the engaged state,
When the speed change lever is positioned in the neutral operation range, the clutch control mechanism disengages the back clutch regardless of movement of the speed change lever between the forward neutral position and the reverse neutral position. Control to switch to the state,
When the shift lever is positioned in the reverse operation area, the clutch control mechanism switches the back clutch to the disengaged state and controls the paddy field work machine. The clutch control mechanism includes a detection body provided on a side of the operation path of the shift lever so as to be swingable across a clutch engagement command area and a clutch release command area, and the detection body as a clutch engagement command area. A biasing mechanism that swings and biases,
When the speed change lever is positioned in the neutral operation range and the reverse operation range, the detection body is swung to the clutch disengagement command range by pressing by the speed change lever,
2. The paddy field work machine according to claim 1, wherein when the shift lever is positioned in the forward operation region, the detection body is swing-operated to the clutch engagement command region by the biasing mechanism.

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